Population in US older than it has ever been

The population in the United States has been aging over the past two decades, and new demographic data shows US people are now older than ever.

The country's median age reached a record high of 38.9 years last year, according to data released on Thursday by the US Census Bureau.

That is an increase of 0.2 years over the previous year and about 3.5 years since 2000. In 1980, the national median age was 30.

"As the nation's median age creeps closer to 40, you can really see how the aging of baby boomers, and now their children — sometimes called echo boomers — is impacting the median age," Kristie Wilder, a demographer in the Census Bureau's Population Division, said in a news release.

One-third of US states had a median age above 40 last year, led by Maine with the highest at 44.8, and New Hampshire at 43.3. Utah had the lowest median age, 31.9 years, followed by the District of Columbia at 34.8 and Texas at 35.5, according to the Census Bureau.

No states experienced a decrease in median age.

Experts attribute the rising median age primarily to low birthrates.

"Birthrates have gradually declined over the past two decades," Wilder said. "Without a rapidly growing young population, the US median age will likely continue its slow but steady rise."

Like many other countries, the US birthrate has been falling almost continuously for more than a decade. The sharp decrease during the recession from 2007 to 2009 was followed by a sustained downward trend. In 2007, the average birthrate was around 2 children per woman. By 2021, it had fallen by more than 20 percent, close to the lowest level in a century.

Thursday's census data also reveals that the US is becoming more diverse. From 2021 to 2022, the Asian population experienced the most significant growth among all racial groups, increasing by 2.4 percent. The Hispanic population followed with a growth of 1.7 percent. The black population grew by 0.9 percent, and the white population by 0.1 percent.

Meanwhile, the new census data also shows that black residents are continuing to leave urban centers in the north and elsewhere.